The plot that organizes the data into 4 groups of equal sizes is box and whisker plot.
The image below shows a box and whisker plot. Following are the elements of box and whisker plot:
Minimum = This is the smallest value of the data set
Q1 = First (Lower) Quartile of the data set. 25% of the data values lie below this point
Q2 = Second Quartile or Median. This is the central value so 50% of the data values lie below this point
Q3 = Third (Upper) Quartile of the data set. 75% of the data values lie below this point.
Maximum = This is the maximum value of the data set.
Based on box and whisker plot we can compare two or more sets of data by comparing the spread of the data. We can also directly observe from the box and whisker plot if the data is uniform, normal or skewed. Using box and whisker plot we can also visualize any outliers that may be in the data.
